[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[netCDF #VMC-329281]: RNetCDF and ncdf4 packages??

This archive contains answers to questions sent to Unidata support through mid-2025. Note that the archive is no longer being updated. We provide the archive for reference; many of the answers presented here remain technically correct, even if somewhat outdated. For the most up-to-date information on the use of NSF Unidata software and data services, please consult the Software Documentation first.

  • Subject: [netCDF #VMC-329281]: RNetCDF and ncdf4 packages??
  • Date: Mon, 04 Apr 2016 10:25:18 -0600
Hello Robert,

We do not maintain either the ncdf4 or RNetCDF packages for R, so I'm afraid I 
cannot say for certain what is happening with your script.  You also don't 
mention specifically what the error is, but I assume that it is a failure to 
set new values in the existing file?  The script you provided *looks* ok, as I 
am familiar with R, but since I don't know anything about the ncdf4 package you 
might contact the maintainer and see if they can provide some insight.

I'm sorry I can't provide a more immediately helpful answer,

-Ward

> Dear UNIDATA,
> I am a graduate student at Vrije Universiteit Brussels and am working with
> NetCDF landsat images in R. I have a problem with writing data into a new
> NetCDF file that i created.
> The aim is to write data at rrc_1609 band and loop this through 62 images.
> below is the script i used.
> kindly assist me. Highly looking forward to your feedback.
> 
> setwd("~/Documents/Landsat")
> #Intall the NetCDF libraries: sudo apt-get install libnetcdf-dev
> #Install the ncdf package in R: install.packages("ncdf4")
> 
> 
> library("ncdf4")
> library("RNetCDF")
> 
> fname<-file.choose()
> fid<-open.nc(fname)
> 
> print.nc(fid)
> newnc<-var.get.nc(fid,"rrc_1609")
> nc_open(newnc)
> 
> # Define netcdf dimensions: name, units and value
> londim1 <- ncdim_def("lon", "degrees_east", 1:3342)
> latdim2 <- ncdim_def("lat", "degrees_north", 1:2213)
> 
> 
> # Define objets of class var.def.ncdf for the netcdf file with its name,
> units, dimension(s) and missing value
> var1 <- ncvar_def("lon", "degrees", londim1, 3342)
> var2 <- ncvar_def("lat", "degrees", latdim2, 2213)
> var3 <- ncvar_def("MYrrc_1609", "-", list(londim1, latdim2), -999, longname
> = "An example of 2-dim variable")
> 
> 
> # Create a netcdf file with its variables var1, var2 and var3
> filename <- ("ncnew.nc")
> ncout<-nc_create("ncnew.nc",var3)
> 
> 
> ncvar_get(ncout)
> 
> nc_close(ncout)
> nc_open(ncout)
> nc_open("ncnew.nc",TRUE)
> ## Write data variables to a netcdf file
> data1<-c(1:3342)
> ncvar_put(ncout,"lon",data1)
> data2<-c(1:2213)
> ncvar_put(ncout,var2,data2)
> data3<-c(1:7395846)
> ncvar_put(ncout,var3,data3)
> 
> ?
> ncnew.nc
> <http://t.sidekickopen50.com/e1t/c/5/f18dQhb0S7lC8dDMPbW2n0x6l2B9nMJW7t5XYg4XXLDdN1qMxhdS9_qqW64JdXC56dxXpf4tsG-d02?t=https%3A%2F%2Fdrive.google.com%2Ffile%2Fd%2F0B2vMX4uM3XVKQzMtLV9ZY2JZQVk%2Fview%3Fusp%3Ddrive_web&si=6132647858798592&pi=f6fdcbe1-763a-4d3e-ba93-7ed75ed5cec2>
> ?
> 
> nc_close(ncout)
> 
> --
> Robert Runya
> MSc O & L,
> Faculty of science & Bioengineering
> Vrije Universiteit Brussels,
> Pleinlaan 2, 1050 Brussels
> Belgium
> 
> Tel; *+32 489689627*
> Email; address@hidden;
> 
> 


Ticket Details
===================
Ticket ID: VMC-329281
Department: Support netCDF
Priority: Normal
Status: Closed